检索结果-南通市图书馆

hierarchical OptimizationMethod for Federated Learning with Feature Alignment and Decision Fusion

Computers, Materials and Continua 2024年第1期81卷 1391-1407页

作者： Li K. Wang X. Wang h. College of Computer Science and Engineering North Minzu University Yinchuan 750021 China The Key Laboratory of Images & Graphics Intelligent Processing of State Ethnic Affairs Commission North Minzu University Yinchuan 750021 China

In the realm of data privacy protection, federated learning aims to collaboratively train a global model. however, heterogeneous data between clients presents challenges, often resulting in slow convergence and inadequate accuracy of the *** shared feature representations alongside customized classifiers for individual clients emerges as a promising personalized solution. Nonetheless, previous research has frequently neglected the integration of global knowledge into local representation learning and the synergy between global and local classifiers, thereby limiting model performance. To tackle these issues, this study proposes a hierarchical optimization method for federated learning with feature alignment and the fusion of classification decisions (FedFCD). FedFCD regularizes the relationship between global and local feature representations to achieve alignment and incorporates decision information from the global classifier, facilitating the late fusion of decision outputs from both global and local classifiers. Additionally, FedFCD employs a hierarchical optimization strategy to flexibly optimizemodel parameters. Through experiments on the Fashion-MNIST, CIFAR-10 and CIFAR-100 datasets, we demonstrate the effectiveness and superiority of FedFCD. For instance, on the CIFAR-100 dataset, FedFCD exhibited a significant improvement in average test accuracy by 6.83% compared to four outstanding personalized federated learning approaches. Furthermore, extended experiments confirmthe robustness of FedFCD across various hyperparameter values. © 2024 The Authors. Published by Tech Science Press.

关键词： data heterogeneity decision fusion feature alignment Federated learning hierarchical optimization

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Compressed Natural Gas (CNG) as a fuel and the associated risks: A quantitative analysis in the scenario of a developing country

引用

JOURNAL OF SAFETY SCIENCE AND RESILIENCE 2024年第3期5卷 306-316页

作者： Ali, Yousaf Younus, Ahsan Khan, Amin Ullah Alrefai, Ahmed h. Fahad Bin Sultan Univ Coll Business & Management POB 15700 Tabuk 71454 Saudi Arabia Ghulam Ishaq Khan GIK Inst Engn Sci & Technol Sch Management Sci Topi Swabi Pakistan Univ Macerata Dept Econ & Law Macerata Italy Fahad Bin Sultan Univ Coll Business & Management Tabuk Saudi Arabia

Excessive dependence on fossil fuels has precipitated various challenges, including Greenhouse Gas (GhG) emissions, health hazards, and the depletion of natural resources. Such perils underscore the importance of conducting requisite risk assessments for alternative fuel sources like Compressed Natural Gas (CNG) to ensure their safe utilization. This study undertakes a quantitative risk assessment encompassing diverse facets of the CNG sector holistically, aiming to pinpoint, analyze, and appraise risks, thus empowering policymakers to devise targeted mitigation strategies. To achieve this goal, the collected data undergoes analysis via an integrated approach combining the Fuzzy Analytic hierarchy Process (F-AhP) and Fuzzy Technique of Order Preference by Similarity to Ideal Solution (F-TOPSIS). The study's findings reveal a heightened risk of explosion within the CNG sector owing to its highly combustible nature. Additionally, it computes an overall risk index of 0.266 for the CNG sector in a developing nation like Pakistan, indicating a relatively lower risk level compared to other fuel sources. Policymakers are thus advised to undertake requisite measures concerning infrastructure, customer safety, and environmental and economic stability to accrue both immediate and long-term benefits. The application of hybrid techniques for the risk assessment of the CNG sector in the case of a developing country marks the novelty of this study and a study of the first of its kind.

关键词： Risk Safety CNG industry Fuzzy Pakistan FUZZY AhP SUPPLY ChAIN MANAGEMENT SYSTEM

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Correlation of work function and stacking fault energy through Kelvin probe force microscopy and nanohardness in diluteα-magnesium

引用

Journal of Magnesium and Alloys 2024年第1期12卷 237-250页

作者： Yigit Türe Ali Arslan Kaya hüseyin Aydin Jiang Peng Servet Turan Eskisehir Technical University Porsuk Vocational SchoolElectronics and Automation DepartmentProgram of MechatronicsEskisehirTurkey Mugla Sitki Kocman University Engineering FacultyMetallurgy and Materials Engineering DepartmentMuglaTurkey hüseying Aydın TUBITAK MRCTurkey Jiang Peng Chongqing UniversityChina Eskisehir Technical University Engineering FacultyMaterials Science and Engineering DepartmentEskisehirTurkey

Electronic interactions of the Group 2A elements with magnesium have been studied through the dilute solid solutions in binary Mg-Ca,Mg-Sr and Mg-Ba *** investigation incorporated the difference in the‘Work Function'(ΔWF)measured via Kelvin Probe Force Microscopy(KPFM),as a property directly affected by interatomic bond types,*** electronic structure,nanoindentation measurements,and Stacking Fault Energy values reported in the *** was shown that the nano-hardness of the solid-solutionα-Mg phase changed in the order of Mg-Ca>Mg-Sr>***,it was shown,by also considering the nano-hardness levels,that SFE of a solid-solution is closely correlated with its‘Work Function'***-hardness measurements on the eutectics andΔWF difference between eutectic phases enabled an assessment of the relative bond strength and the pertinent electronic structures of the eutectics in the three *** withΔWF and at least qualitative verification of those computed SFE values with some experimental measurement techniques were considered important as those computational methods are based on zero Kelvin degree,relatively simple atomic models and a number of *** asserted by this investigation,if the results of measurement techniques can be qualitatively correlated with those of the computational methods,it can be possible to evaluate the electronic structures in alloys,starting from binary systems,going to ternary and then multi-elemental *** investigation has shown that such a qualitative correlation is *** all,the SFE values are not treated as absolute values but rather become essential in comparative investigations when assessing the influences of alloying elements at a fundamental level,that is,free electron density *** study indicated that the principles of‘electronic metallurgy'in developing multi-elemental alloy systems can be followed via practical experimental methods,i.e.ΔWF measurements using KPF

关键词： Mg alloys Dilute alloys Work function Stacking fault energy Kelvin probe force microscopy Short range order Miedema Nanoindentation Eutectics

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Reactive destabilization and bidirectional catalyzation for reversible hydrogen storage of LiBh_(4) by novel waxberry-like nano-additive assembled from ultrafine Fe_(3)O_(4) particles

引用

Journal of Materials Science & Technology 2024年第6期173卷 63-71页

作者： S.Wang M.h.Wu Y.Y.Zhu Z.L.Li Y.X.Yang Y.Z.Li h.F.Liu M.X.Gao Department of Material Science Shenzhen MSU-BIT UniversityShenzhen 518172China State Key Laboratory of Silicon and Advanced Semiconductor Materials&School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China Institute of Resources Utilization and Rare Earth Development State Key Laboratory of Rare Metals Separation and Comprehensive UtilizationGuangdong Provincial Key Laboratory of Rare Earth Development and ApplicationGuangdong Academy of SciencesGuangzhou 510650China Institute of Science and Technology for New Energy Xi’an Technological UniversityXi’an 710021China National Supercomputing Center in Shenzhen Shenzhen 518055China

LiBh_(4) containing 18.5 wt.%h_(2) is an attractive high-capacity hydrogen storage material,however,it suffers from high operation temperature and poor ***,a novel and low-cost bifunctional additive,waxberry-like Fe_(3)O_(4) secondary nanospheres assembled from ultrafine primary Fe_(3)O_(4) nanoparticles,is synthesized,which exhibits significant destabilization and bidirectional catalyzation towards(de)hydrogenation of LiBh_(4).With an optimized addition of 30 wt.% waxberry-like Fe_(3)O_(4),the system initiated dehydrogenation below 100℃ and released a total of 8.1 wt.%h_(2) to 400℃.After 10 cycles,a capacity retention of 70% was achieved,greatly superior to previously reported oxides-modified *** destabilizing and catalyzing mechanisms of waxberry-like Fe_(3)O_(4) on LiBh_(4) were systematically analyzed by phase and microstructural evolutions during dehydrogenation and hydrogenation cycling as well as density functional theory(DFT)*** present work provides new insights in developing advanced nano-additives with unique structural and multifunctional designs towards LiBh4 hydrogen storage.

关键词： LiBh_(4) hydrogen storage Waxberry-like Fe_(3)O_(4) Destabilization Catalysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Net effect of air pollution controls on health risk in the Beijing-Tianjin-hebei region during the 2022 winter Olympics and Paralympics

引用

Journal of Environmental Sciences 2024年第1期135卷 560-569页

作者： Changqing Lin Peter K.K.Louie Alexis K.h.Lau Jimmy C.h.Fung Zibing Yuan Minghui Tao Xuguo Zhang Md.Shakhaoat hossain Chengcai Li Xiang Qian Lao Division of Environment and Sustainability The Hong Kong University of Science and TechnologyHong KongChina Environmental Protection Department Hong Kong Government SARHong KongChina Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong KongChina Guangdong-hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality The Hong Kong University of Science and TechnologyHong KongChina Department of Mathematics The Hong Kong University of Science and TechnologyHong KongChina School of Environment and Energy South China University of TechnologyGuangzhou 510006China hubei Key Laboratory of Critical Zone Evolution School of Geography and Information EngineeringChina University of GeosciencesWuhan 430074China Department of Public health and Informatics Jahangirnagar UniversityDhaka 1342Bangladesh Department of Atmospheric and Oceanic Sciences School of PhysicsPeking UniversityBeijing 100871China Jockey Club School of Public health and Primary Care The Chinese University of Hong KongHong KongChina

Due to the non-linearity in ozone(O_(3))formation,reducing the emission of nitrogen oxides(NO_(x))may increase O_(3) *** the counteractive O_(3) response to NO_(x) reduction,overall impact of air pollution controls can be ambiguous when the assessments focus on the changes in pollutant *** this study,a risk-based method was used to gauge the net effect of air pollution controls on mortality risk in the Beijing–Tianjin–hebei(BTh)region during the 2022 Winter Olympics and Paralympics(WOP).This mega-event presents a unique opportunity to investigate the efficacy of deep cuts in pollutant *** show that O_(3) concentrations greatly increased as nitrogen dioxide(NO_(2))concentrations decreased in the *** to the active photochemical formations,O_(3) became the dominant pollutant that affected human health during the *** the substantial O_(3) increases,the health benefits of NO_(2) reductions overwhelmed the adverse health effects of O_(3) increases in most regions of the BTh(at 81 out of 112 stations).After considering the impacts of particulate matter,the integrated health risk of air pollution mixtures declined almost everywhere in the *** results underscore the great necessity of changing the assessment paradigm of pollution control from using concentration-based methods to using risk-based *** with the carbon neutrality policy,stringent control of NO_(x)emission from combustion sources is a promising way to achieve synergistic control solutions for air pollution and climate change.

关键词： Ozone Nitrogen dioxide health risk Carbon neutrality Mega-events

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

引用

Matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： Y.X.Wang X.L.Zhu S.M.Weng P.Li X.F.Li h.Ai h.R.Pan Z.M.Sheng Key Laboratory for Laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of Laser Fusion of China Academy of Engineering Physics MianyangSichuan 621900China State key Laboratory of high Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(Thz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or Thz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or Thz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and Thz spectral ranges.

关键词： laser ultrashort photon

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Atomistic Investigation of Shock-Induced Amorphization within Micro-shear Bands in hexagonal Close-Packed Titanium

引用

Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1590-1600页

作者： Z.C.Meng K.G.Wang T.Ali D.Li C.G.Bai D.S.Xu S.J.Li A.h.Feng G.J.Cao J.h.Yao Q.B.Fan h.Wang R.Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Interdisciplinary Centre for Additive Manufacturing(ICAM) School of Materials and ChemistryUniversity of Shanghai for Science and TechnologyShanghai 200093China School of Materials Science and Engineering Tongji UniversityShanghai 201804China Key Laboratory for Light-Weight Materials Nanjing Tech UniversityNanjing 210009China National Key Laboratory of Science and Technology on Materials Under Shock and Impact School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401135China

The mechanical response of a single crystal titanium sample against(0001)α surface impact was investigated using molecular dynamics ***,non-uniform plastic deformation was observed in the *** high strain rates,amorphization occurred near the edge of the contact region where severe shear strain induced a large number of stacking faults(SFs)and *** contrast,the central part of the contact region underwent less deformation with significantly fewer ***,instead of amorphization by consuming SFs and dislocations,there was a gradual increase in the density of dislocations and SFs during the process of *** local amorphous regions eventually grew into shear bands.

关键词： Shock compression Amorphization Shear band Titanium Molecular dynamics

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Efficient guiding and focusing of intense laser pulse using periodic thin slits

引用

Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.W.huang K.Jiang C.N.Wu h.Peng P.C.hen R.Li h.B.Zhuo C.T.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Facies development and sedimentology of the Middle Miocene carbonates of the Raghama Formation, northeastern Saudi Arabia

引用

Acta Geochimica 2024年第1期43卷 87-96页

作者： Mansour h.Al-hashim Abdelbaset S.El-Sorogy Meshal Wadani Department of Geology and Geophysics College of ScienceKing Saud University2455Riyadh 11451Saudi Arabia

Ragahama Formation comprises a siliciclastic continental deposits followed by marine carbonates, representing prograding alluvial fans from adjacent high hinterlands seaward into lagoons and fringing reef environments. The present work aimed to document the facies development and sedimentology of the Raghama carbonates exposed along the eastern coastal plain of the Red Sea, northwestern Saudi Arabia. Four stratigraphic sections were measured and sampled(D1–D4) and thin sections and major and trace element analyses were prepared and applied for petrographic and geochemical approaches. The carbonates were subdivided into three successive fore-reef, reef-core, and back-reef depositional facies. Sandy stromatolitic boundstone, microbial laminites, dolomitic ooidal grainstone, bioclastic coralline algal wackestone, sandy bioclastic wackestone, and coral boundstones were the reported microfacies types. Petrographic analysis reveals that the studied carbonates were affected by dissolution, dolomitization, and aggrading recrystallization, which affects both the original micrite matrix and grains or acts as fracture and veinlet filling leading to widespread vuggy and moldic porosity. No evidence of physical compaction, suggesting rapid lithification and recrystallization during early diagenesis and prior to substantial burial and intensive flushing by meteoric waters. Most of the original microstructure of corals were leached and destructed. This is indicated by the higher depletion in Sr and Ca levels and increase in Mg,Na, Fe, and Mn levels, especially in section D1, in comparison with the worldwide carbonates.

关键词： Raghama Formation Miocene Diagenesis Geochemistry Saudi Arabia

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Long Term X-Ray Spectral Variations of the Seyfert-1 Galaxy Mrk 279

引用

Research in Astronomy and Astrophysics 2024年第6期24卷 307-314页

作者： K.Akhila Ranjeev Misra Savithri h.Ezhikode K.Jeena Department of Physics Providence Women’s CollegeUniversity of CalicutKerala 673009India Inter-University Centre for Astronomy and Astrophysics(IUCAA) PB No.4GaneshkhindPune 411007India Department of Physics and Electronics CHRIST(Deemed to be University)Hosur Main RoadBangalore 560029India

We present the results from a long term X-ray analysis of Mrk 279 during the period 2018–*** use data from multiple missions–AstroSat,NuSTAR and XMM-Newton,for the *** X-ray spectrum can be modeled as a double Comptonization along with the presence of neutral Fe Kαline emission,at all *** determined the source’s X-ray flux and luminosity at these different *** find significant variations in the source’s flux *** also investigate the variations in the source’s spectral components during the observation *** find that the photon index and hence the spectral shape follow the variations only over longer time *** probe the correlations between fluxes of different bands and their photon indices,and found no significant correlations between the parameters.

关键词： galaxies:Seyfert galaxies:individual(Mrk 335) X-rays:galaxies

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：